A 911 tape from a smoke and fog shrouded Florida highway revealed the terror of crashed motorists as they heard cars and trucks smashing into things around them, but unable to see what was happening.

By the end of the call, one woman witnessed or heard a half dozen collisions, can hear injured people crying for help somewhere on the murky highway, and is sobbing into the phone.

Police suspect an arsonist may have started a smokey Florida brush fire that helped blind drivers on Interstate 75 south of Gainesville, turning the highway into a death trap late Saturday night and into Sunday morning as drivers of cars and tractor trailers smashed into each other.

Ten people died and 18 were injured. Several are still in the hospital.

"If it were arson, and we could determine who caused the fire, it would be manslaughter," Art Forgy of the Alachua County Sheriff's department told ABC News.

Alachua County released a 911 tape from a motorist who had slammed into a guardrail and had called for help. During the call, the woman gets increasingly frightened as other vehicles can be heard plowing into each other.

When asked if anyone was injured, the caller tells the operator, "No, no thank God. But I think I heard another crash back there."

The operator urges the woman to stay in her vehicle and that help is on the way, but the woman keeps talking, saying, "It's really bad out here. People are just stopping."

The 911 dispatcher tells the woman "a lot of lines ringing right now," so the operator has to get off, but the sound of another crash is heard.

The caller continues, "Oh my goodness. And that was a truck! ... You can't see. You cannot see. It's like impossible to see."

The operator now gives the driver new instructions. "All right, I want you, if you are able to, turn on your emergency flashers, get out of your vehicle and step as far away from traffic as..." but moments later another crash is heard.

At least three more crashes are audible during the increasingly hectic call. The woman who dialed 911 is getting upset and is heard telling the dispatcher, "You can hardly even see your hazards. Here comes another one. He's coming too fast. Here comes another one," followed by the sound of yet another collision.

The dispatcher is heard telling the driver that many ambulances are being sent. "Please yes. Oh wow," she replies. She is left crying and telling the operator she can hear injured people crying for help.

It wasn't clear what started the brush fire, but officials suspect it may have been intentionally set because there had been no controlled burns in the area and no lightning strikes.

Officials believe the brush fire was started at around 3 p.m. Saturday, creating a uniquely soupy combination that plagues Florida this time of year when smoke from brush fires mixes with the dense moisture coming off of marshes, swamps, bogs and lakes.

By midnight two crashes had closed I-75. Then as the smokefog got even more dense the massive pileup began.

The crashes set some of the vehicles on fire. One of the first to burst into flames was a FedEx truck, Forgy said. It likely began a "domino effect" with cars and trucks going from nearly 70 mph to a dead standstill in seconds. Vehicles ended up spearing others, pancaked under semi trailers and stacking up on each other.

The vehicles were so mangled and so charred that it took investigators more than 24 hours to identify the dead. The scene was so chaotic that investigators are still trying to determine the chronology of the accident.

Lt. Pat Riordan of the Florida Highway Patrol said "this was the worst I've seen in 27 years on the job." When rescuers first arrived, the superfog and smokefog were so thick they had to locate victims by their screams.

The Florida Highway Patrol and various sheriff's offices continue to investigate the crash.